Stacking paperboard container



Aug. 7, 1956 J. w. MAIN 2,757,853

- STACKING PAPERBYOARD CONTAINER Filed Feb. 19. 1953 x 3 Sheets-Sheet 1INVENTQR.

7, 1956 J. w. MAIN 2,757,853

- STACKING PAPERBOARD CONTAINER Filed Feb. 19. 1953 5 Sheets-Sheet 3 INV EN TOR.

mwmwwga United States Patent STACKING PAPERBOARD CONTAINER James W.Main, Bellevue, Wash., assignor to Container Corporation of America,Chicago, 11]., a corporation of Delaware Application February 19, 1953,Serial No. 337,729

2 Claims. (Cl. 229-39) This invention relates to containers for use inhandling and shipping fruits, vegetables and other agricultural productsas well as, if desired, manufactured products.

The container of my invention, in its preferred form, is open topped andis particularly suitable for handling and shipping fruits and otheragricultural products, such containers being frequently termed lugs. Myinvention is directed to a container of the character stated which isformed of paperboard or analogous material, is well adapted to stacking,possesses adequate mechanical strength, and has provision for readycirculation of air about and between the containers of a stack thereof.The container is formed from a one piece paperboard blank cut and scoredto provide stacking panels at the tops of the ends of the container, anda bottom closure wall bulged down ward below the ends and sides of thecontainer and disposed to contact the inner faces of the upper portionsof the ends of a similar and subjacent container, for stacking. Thebottom wall is of three thicknesses of paperboard, for the major portionof its extent, to provide adequate load supporting strength while alsocausing downward bulging thereof as and for the purpose above stated.The sides and the ends of the container are double walled, the innerpanels of the sides restrain the inner closure flaps of the bottom wallagainst upward movement, the inner panels of the ends hold the innerpanels of the sides in down folded effective position, and the ends haveat the tops thereof stacking panels provided with end extensions seatingon the sides and restraining the inner side panels against upwardmovement while cooperating therewith for reinforcing the ends. Thebottom wall further comprises two outer closure flaps secured togetherby tongue and slot means and providing with the inner flaps a bottomwall of triple thickness, the outer flaps having at the ends of theouter sides thereof extensions disposed to seat on the end extensions ofthe end wall stacking panels for spacing apart the containers of astack, for free circulation of air between the stacked containers.Further objects and advantages of my invention will appear from thedetail description.

In the drawings:

Figure 1 is a perspective view of a container embodying my invention;

Figure 2 is an end view of the container of Figure 1;

Figure 3 is a bottom view, partly broken away, of the container ofFigures land 2; r A

Figure 4 is a side view of two containers like that of Figure 1, stackedone on the other, with the lower container partly broken away;

Figure 5 is an end View of the two stacked containers of Figure 4;

Figure 6 is a fragmentary sectional view, on an enlarged scale, takensubstantially on line 66 of Figure 5; and

Figure 7 is a plan view of the blank from which the container is formed.

The container is formed from a rectangular blank, such as that shown inFigure 7, formed from paperboard or analogous suitable material. Indescribing the blank the ice various elements thereof will be referredto in relation to the positions which they occupy in the completedcontainer. Referring further to Figure 7, the blank preferably is formedfrom a sheet of double faced corrugated paperboard and is cut and scoredto provide outer side wall panels 8 and 9, outer end wall panels 10 and11 attached to the panels 8 and 9 along fold lines 12, and a securingflap 13 attached to the outer end of panel 8 along a fold line 14. Innerside wall panels 15 are attached to the upper edges of the panels 8 and9 by narrow strip or fold panels 16 defined by fold lines 17 at theupper edges of panels 8 and 9 and fold lines 18 parallel with and spaceda short distance from the fold lines 17. Inner end wall panels 19 areattached to the upper edges of the outer end wall panels 10 and 11 byrelatively narrow seat panels 20 defined by fold lines 21 at the upperedges of panels 10 and 11 and fold lines 22 parallel with and spacedfrom the fold lines 21. The seat panels 20 are of materially greaterwidth than the fold panels 16, as shown, and the inner end wall panels19 are of less width than the outer end wall panels 10 and 11, each ofthe seat panels 20 being provided, at each end thereof, with anextension 23, preferably of rounded shape as shown, the outer edge ofwhich is substantially coincident with the corresponding fold line 12,with the exception of the extension 23 at the outer end of the stackingpanel 20 attached to the outer end panel 11, the outer end of the lastmentioned extension 23 being substantially coincident with the outeredge of panel 11.

Inner bottom closure flaps 24 and 25 are attached to the lower edges ofthe outer end wall panels 10 and 11, re spectively, along fold lines 26and 27. The flaps 24 and 25 correspond in width to the outer end wallpanels 10 and 11 and each is of a length equal to one half the length ofeach of the outer side wall panels 8 and 9, the two latter panels beingof the same length. The substantially rectangular first or upper outerbottom closure flap 29 is attached to the lower edge of the outer sidewall panel 8 along a fold line 341 and a second or lower substantiallyrectangular outer bottom closure flap 31 is attached to the lower edgeof the outer side wall panel 9 along a fold line 32, the fold lines 30and 32 constituting extensions of the fold lines 26 and 27. The upperouter bottom closure flap 29 is of less length than the attached panel 8for the major portion of its length, with its end spaced inward from theends of panel 8 a distance approximating the width of the respectivestacking panels 20. Flap 29 is provided at its outer side and at eachend thereof with an extension 33, the outer edges of extension 33 beingsubstantially coincident with the fold lines 12 and 14, respectively.The outer bottom closure flap 29 is further provided with twotransversely extending inclined slots 35 of substantial length, theouter ends of which are spaced a short distance inwardly from the outeredge of the flap 29 defined by the fold line 30, The second or lowerouter bottom closure flap 31 is also provided, at each end of its outerside, with an extension 36, the outer ends of extensions 36 beingsubstantially coincident with the fold lines 12 at the ends of the outerside wall panel 9. The flap 31 is further provided, atabout themid-width of each end thereof, with an outwardly flaring notch 37 andthe inner corner portions of fiap 31 constitute locking tongues 38 whichmay be flexed or bent along lines indicated by the dotted lines 39, for.insertion through the slots 35 of the first outer bottom closure flap29, as will appear more fully later.

In setting up the blank to provide the container, the securing flap 13may be folded upwardly onto the outer side wall panel 8 and the panels 9and 11 may then be foldeddownwardly onto the panels 10 and 8, with panelI 11' seating on the flap 13, and flap 13 is thensuitably secured topanel 11, conveniently by means of staples 40. Thereafter the partiallyfolded and secured blank is expanded so as to dispose the outer sidewall panels 8 and 9 in parallel spaced relation with the outer end wallpanels 10 and 11 extending between and connecting the side wall panelsand also disposed in parallel spaced relation. The inner bottom closureflaps25 and 24 are then folded upward into position between the panels 8and 9, after which the first or upper outer bottom closure flap 29 isfolded upward in underlying relation to the inner bottom closure flaps24 and 25. The second or lower outer bottom closure flap 31 is thenfolded upwardly into underlying relation to the flap 29, the cornerportions 38 of flap 31 being first flexed or bent along the dotted lines39 and inserted through the slots 35 of flap 29. Thereafter, the flap 31is moved into position seating on the outer face of flap 29, the lockingtongue portions 38 of flap 31 being thereby fully inserted through theslots 35 with the portions of flap 29 at the inner ends of slots 35entering the notches 37 and in cooperation therewith providing positivelocking means effective for locking the flaps 29 and 31 together andpreventing casual withdrawal of the locking tongues 38 from the slots35. The bottom of the partially assembled container then appears as inFigure 3. Thereafter the inner side wall panels 15 are folded downwardand inward against the panels 8 and 9 and the inner end wall panels 19are then folded downward and inward between the panels 15 and about thefold lines 21 and 22. The panels 19 have a friction fit between thepanels 15 effective for holding the latter in folded down position and,also, for holding the panels 19 in folded down position. The particularorder in which the panels and flaps of the blank are folded need not bethat above stated, which is by way of description only. If desired, theinner side wall and end wall panels may be first folded into the bodyportion of the container, after which the bottom wall structurecomprising the closure flaps 24, 25, 29 and 31 may be folded and securedtogether in the manner above described.

In the completed container, the end extensions 23 of the seating panelsoverlie and seat upon the end portions of the fold panels 16, as shownin Figure l, the lower edges of the panels 15 seat upon the upper facesof the flaps 24 and 25 so as to restrain them against upward movement,and the inner end wall panels 19 extend at a downward and outwardinclination from the inner edges of the seating panels 20 and seat attheir lower edges on the flaps 24 and 25 adjacent the fold lines 26 and27, respectively. The panels 19 thus provide inclined trusses extendingfrom the inner edges of the seating panels 20 and capable of supportingsubstantial loads, and the end extensions 23 of the seating panels 20are supported by the side Walls comprising the panels 15 and 8 and 9,respectively, so as to impart additional load supporting strength to theseating panels 20. r

In the assembled container, the locking tongues 38 of the lower bottomclosure flap 31 are disposed between the corresponding areas of flap 29and the inner bottom closure flaps 24 and 25, and the portions of flap29 between and extending inwardly between the slots 35 thereof aredisposed between the flap 31 and the inner bottom closure flaps 25 and24. The bottom wall of the container, at the end portions thereof isthus of three thicknesses of paperboard as shown in Figures 3 and 6.That causes a distinct downward bulge of the ends of the bottom wall toa material distance below the lower edges of the side and end walls ofthe container body. Further, due to the inherent resiliency of thecorrugated paperboard, the locking tongues 38 also exert downwardpressure which further contributes to the downward bulging of the endsof the bottom wall. The net result is that the ends of the bottom wallare bulged downward to a sufficient extent to assure contact thereofwith the inner faces of the upper or top portions of the inner end wallpanels 19 when the container is stacked upon another similar container.

As previously noted, the outer bottom closure flaps 29 and 31 have theirends spaced inward from the ends of the outer side wall panels 8 and 9,respectively, a distance approximately equal to the width of therespective stacking panels 20. Accordingly, when the container isstacked upon another similar container, the extensions 33 of the bottomwall of the upper container seat upon the end extensions 23 of thestacking panels 20 of the lower container, with the end portions of thebottom wall of the upper container extending downward between thestacking panels 20 of the lower container and disposed to contact theinner faces of the inner end wall panels 19 adjacent the top thereof.That effectively restrains the upper container against endwise movementrelative to the lower container, as will be clear from Figures 4 and 6.Further, the bottom wall extensions 33 and the end extensions 23 of thestacking panels 20 provide spacing elements which space the side and endwalls of the upper container from the side and end walls of the lowercontainer, providing openings or spaces 42 and 43 therebetween at thesides and the ends thereof. Those spaces permit free circulation of airbetween the stacked containers and over and about the contents thereof,which is frequently desirable for maintaining the contents, such asfruit and vegetables, of the containers in fresh condition. In view ofthe fact that the upper container seats upon the end extensions 23 ofthe stacking panels 20 of the lower container, and the extensions 23seat upon the ends of the fold flaps 16 of the side walls of thecontainer, the weight of the loaded upper container is effective forresisting any tendency to upward movement of the inner side wall panels15 of the lower container, thus assuring that the bottom wall of thelower container will be maintained in its downwardly bulged condition atthe end portions thereof for contact with the inner faces of the endwalls of the next lower container of a stack, as above described.

In Figure 7 the dotted lines 39 indicate the lines along which thelocking tongues 38 are flexed or bent for insertion through slots 35 offlap 29. If desired, the flap 31 may be scored along lines 39, tofacilitate insertion of tongues 38 through slots 35. Such scoring is notessential and may be omitted to advantage in certain cases, so as toobtain the full benefit of the inherent resiliency of the paperboard forbulging the end portions of the bottom downward. The end wall panels 10and 11 are cut to provide tabs 45 attached to the upper portions thereofand foldable inward and upward to provide openings 46 for hand holds.

It will be understood that changes in detail may be resorted to withoutdeparting from the field and scope of my invention, and I intend toinclude all such variations, as fall within the scope of the appendedclaims, in this application in which the preferred form only of myinvention has been disclosed.

I claim:

1. In a paper board container adapted for stacking, an open top bodysubstantially rectangular in plan comprising side walls, end wallsprovided at the tops thereof with inwardly extending horizontal seatingpanels of substantial width providing end seating surfaces for the endportions of a superjacent container, inner bottom closure flapsrespectively hinged to the lower edges of said end walls, an upper outerbottom closure flap hinged to the lower edge of one of said side wallsand underlying said inner flaps, and a lower outer bottom closure flaphinged to the lower edge of the other side wall and underlying saidupper outer flap, said outer bottom closure ilaps respectivelycomprising a relatively narrow outer portion hinged at its outer sideedge to the lower edge of the corresponding side wall and a relativelywide rectangular inner portion of substantially uniform width, the endsof said inner portions of said outer bottom closure flaps being spacedinwardly from said end walls a distance approximately equal to the widthof the respective seating panels, said upper outer closure flap beingprovided adjacent each end of said inner portion thereof with aninclined slot and the inner corner portions of said inner portion ofsaid lower outer bottom closure flap being inserted through said slots,said inner and outer bottom closure flaps together providing a bottomwall of triple thickness for the major portion of its extent with theends of said inner portions of said outer bottom closure flaps boweddownward beyond said outer portions thereof and beyond said end wallsand disposed for endwise contact with the inner faces of the end wallsof a similar subjacent container adjacent the end seating surfacesthereof.

2. In a paper board container adapted for stacking, an open top bodysubstantially rectangular in plan comprising side walls, end wallsprovided at the tops thereof with inwardly extending horizontal seatingpanels of substantial width overlying at their ends the end portions ofsaid side walls and providing end seating surfaces for the end portionsof a superjacent container, inner bottom closure flaps respectivelyhinged to the lower edges of said end walls, an upper outer bottomclosure flap hinged to the lower edge of one of said side walls andunderlying said inner flaps, and a lower outer bottom closure flaphinged to the lower edge of the other side wall and underlying saidupper outer flap, said outer bottom closure flaps respectivelycomprising a relatively narrow outer portion hinged at its outer sideedge to the lower edge of and of approximately the same length as thecorresponding side wall and a relatively wide rectangular inner portionof substantially uniform width, the ends of said inner portions of saidouter bottom closure flaps being spaced inwardly from said end walls adistance approximately equal to the width of the respective seatingpanels, said upper outer closure flap being provided adjacent each endof said inner portion thereof with an inclined slot and the inner cornerportions of said inner portion of said lower outer bottom closure flapbeing inserted through said slots, said inner and outer bottom closureflaps together providing a bottom wall of triple thickness for the majorportion of its extent with the ends of said inner portions of said outerbottom closure flaps bowed downward beyond said outer portions thereofand beyond said end walls and disposed for endwise contact with theinner faces of the end walls of a similar subjacent container adjacentthe end seating surfaces thereof, the end portions of said relativelynarrow outer portions of said outer bottom flaps being disposed to seaton said end portions of said seating panels of a similar subjacentcontainer for spacing stacked containers apart and thereby providing aspace for ventilation between adjacent stacked containers.

References Cited in the file of this patent UNITED STATES PATENTS288,254 Munson Nov. 13, 1883 1,234,483 Luke July 24, 1917 1,715,583Warren June 4, 1929 1,735,682 Hess Nov. 12, 1929 1,797,594 Taube et alMar. 24, 1931 1,968,082 Jensen July 31, 1934 1,997,909 Luce Apr. 16,1935 2,031,834 Klefeker Feb. 25, 1936 2,326,926 Bureau et al Aug. 17,1943 2,339,224 Shina Jan. 11, 1944 2,349,241 Arneson May 23, 19442,543,698 Lebold Feb. 27, 1951

